<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Auth
 * @subpackage Zend_Auth_Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Digest.php 16200 2009-06-21 18:50:06Z thomas $
 */


/**
 * @see Zend_Auth_Adapter_Interface
 */
require_once 'Zend/Auth/Adapter/Interface.php';


/**
 * @category   Zend
 * @package    Zend_Auth
 * @subpackage Zend_Auth_Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Auth_Adapter_Digest implements Zend_Auth_Adapter_Interface
{
	/**
	 * Filename against which authentication queries are performed
	 *
	 * @var string
	 */
	protected $_filename;

	/**
	 * Digest authentication realm
	 *
	 * @var string
	 */
	protected $_realm;

	/**
	 * Digest authentication user
	 *
	 * @var string
	 */
	protected $_username;

	/**
	 * Password for the user of the realm
	 *
	 * @var string
	 */
	protected $_password;

	/**
	 * Sets adapter options
	 *
	 * @param  mixed $filename
	 * @param  mixed $realm
	 * @param  mixed $username
	 * @param  mixed $password
	 * @return void
	 */
	public function __construct($filename = null, $realm = null, $username = null, $password = null)
	{
		$options = array('filename', 'realm', 'username', 'password');
		foreach ($options as $option) {
			if (null !== $$option) {
				$methodName = 'set' . ucfirst($option);
				$this->$methodName($$option);
			}
		}
	}

	/**
	 * Returns the filename option value or null if it has not yet been set
	 *
	 * @return string|null
	 */
	public function getFilename()
	{
		return $this->_filename;
	}

	/**
	 * Sets the filename option value
	 *
	 * @param  mixed $filename
	 * @return Zend_Auth_Adapter_Digest Provides a fluent interface
	 */
	public function setFilename($filename)
	{
		$this->_filename = (string) $filename;
		return $this;
	}

	/**
	 * Returns the realm option value or null if it has not yet been set
	 *
	 * @return string|null
	 */
	public function getRealm()
	{
		return $this->_realm;
	}

	/**
	 * Sets the realm option value
	 *
	 * @param  mixed $realm
	 * @return Zend_Auth_Adapter_Digest Provides a fluent interface
	 */
	public function setRealm($realm)
	{
		$this->_realm = (string) $realm;
		return $this;
	}

	/**
	 * Returns the username option value or null if it has not yet been set
	 *
	 * @return string|null
	 */
	public function getUsername()
	{
		return $this->_username;
	}

	/**
	 * Sets the username option value
	 *
	 * @param  mixed $username
	 * @return Zend_Auth_Adapter_Digest Provides a fluent interface
	 */
	public function setUsername($username)
	{
		$this->_username = (string) $username;
		return $this;
	}

	/**
	 * Returns the password option value or null if it has not yet been set
	 *
	 * @return string|null
	 */
	public function getPassword()
	{
		return $this->_password;
	}

	/**
	 * Sets the password option value
	 *
	 * @param  mixed $password
	 * @return Zend_Auth_Adapter_Digest Provides a fluent interface
	 */
	public function setPassword($password)
	{
		$this->_password = (string) $password;
		return $this;
	}

	/**
	 * Defined by Zend_Auth_Adapter_Interface
	 *
	 * @throws Zend_Auth_Adapter_Exception
	 * @return Zend_Auth_Result
	 */
	public function authenticate()
	{
		$optionsRequired = array('filename', 'realm', 'username', 'password');
		foreach ($optionsRequired as $optionRequired) {
			if (null === $this->{"_$optionRequired"}) {
				/**
				 * @see Zend_Auth_Adapter_Exception
				 */
				require_once 'Zend/Auth/Adapter/Exception.php';
				throw new Zend_Auth_Adapter_Exception("Option '$optionRequired' must be set before authentication");
			}
		}

		if (false === ($fileHandle = @fopen($this->_filename, 'r'))) {
			/**
			 * @see Zend_Auth_Adapter_Exception
			 */
			require_once 'Zend/Auth/Adapter/Exception.php';
			throw new Zend_Auth_Adapter_Exception("Cannot open '$this->_filename' for reading");
		}

		$id       = "$this->_username:$this->_realm";
		$idLength = strlen($id);

		$result = array(
            'code'  => Zend_Auth_Result::FAILURE,
            'identity' => array(
                'realm'    => $this->_realm,
                'username' => $this->_username,
		),
            'messages' => array()
		);

		while ($line = trim(fgets($fileHandle))) {
			if (substr($line, 0, $idLength) === $id) {
				if (substr($line, -32) === md5("$this->_username:$this->_realm:$this->_password")) {
					$result['code'] = Zend_Auth_Result::SUCCESS;
				} else {
					$result['code'] = Zend_Auth_Result::FAILURE_CREDENTIAL_INVALID;
					$result['messages'][] = 'Password incorrect';
				}
				return new Zend_Auth_Result($result['code'], $result['identity'], $result['messages']);
			}
		}

		$result['code'] = Zend_Auth_Result::FAILURE_IDENTITY_NOT_FOUND;
		$result['messages'][] = "Username '$this->_username' and realm '$this->_realm' combination not found";
		return new Zend_Auth_Result($result['code'], $result['identity'], $result['messages']);
	}
}
